MAINT: bump matplotlib from 3.5.3 to 3.8.1

Bumps [matplotlib](https://github.com/matplotlib/matplotlib) from 3.5.3 to 3.8.1.
- [Release notes](https://github.com/matplotlib/matplotlib/releases)
- [Commits](matplotlib/matplotlib@v3.5.3...v3.8.1)

---
updated-dependencies:
- dependency-name: matplotlib
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

pyproject.toml

@@ -41,7 +41,7 @@ tests = [
     "joblib==1.3.2",
     "matplotlib==3.5.3; python_version == '3.7'",
     "matplotlib==3.7.3; python_version == '3.8'",
-    "matplotlib==3.8.0; python_version > '3.8'",
+    "matplotlib==3.8.1; python_version > '3.8'",
     "numpy==1.21.6; python_version <= '3.9'",
     "numpy==1.26.0; python_version > '3.9'",
     "mock",
@@ -72,7 +72,7 @@ doc = [
     "jupyterlab==4.0.6",
     "matplotlib==3.5.3; python_version == '3.7'",
     "matplotlib==3.7.3; python_version == '3.8'",
-    "matplotlib==3.8.0; python_version > '3.8'",
+    "matplotlib==3.8.1; python_version > '3.8'",
     "nbsphinx==0.9.3",
     "numpydoc==1.5.0; python_version == '3.7'",
     "numpydoc==1.6.0; python_version > '3.7'",
@@ -104,7 +104,7 @@ full = [
     "imageio",
     "matplotlib==3.5.3; python_version == '3.7'",
     "matplotlib==3.7.3; python_version == '3.8'",
-    "matplotlib==3.8.0; python_version > '3.8'",
+    "matplotlib==3.8.1; python_version > '3.8'",
     "numpy==1.21.6; python_version <= '3.9'",
     "numpy==1.26.0; python_version > '3.9'",
     "pandas==1.3.5; python_version == '3.7'",